Limekiln.



No. 797.537. PATENTED AUG. 15, 1905- S. W. SHOOP.

LIMBKILN.

APPLIOATION FILED AUG115, 1904.

2 SHEETS-SHEET 2.

AnlREW m. GRAMM co. vwm-mmcmwnsas. wumnmon, o c

SAUL W. SHOOP, OF FRONT ROYAL, VIRG-INlA.

LlEl (lLN.

Specification of Letters Patent.

Patented Aug. .15, 1905.

Application filed August 15, 1904. $erial No, 220,847. Substituted forabandoned application filed lpril 27, 1904:, Serial No. 205,085.

"0 a, whom 711; may concern:

Be it known that I, SAUL W. SI-ioor, a citizen of the United States,residing at Front Royal, in the county of Warren and State of Virginia,have invented certain new and useful Improvements in Limekilns, of whichthe following is a specification.

My said invention consists in certain im provements in the constructionand arrangement of limekilns whereby either a natural or a forced draftis provided therefor of improved effect and interchangeably arranged,thus enabling the operation of the limekiln to be carried on under anatural draft when suflicient with more satisfactory results than havebeen heretofore attained and the forced draft applied when needed, allas will be hereinafter more fully described and claimed.

Referring to the accompanying drawings, which are made a part hereof andon which similar reference characters indicate similar parts, Figure 1is a front elevation of a limekiln constructed to embody theimprovements constituting my present invention, and Fig. 2 a transversevertical section through the same on the dotted line 2 2.

In said drawings the portion marked A represents the barrel of the kiln,B the furnace portion, and C the ash pit portion. The barrel A may be ofany preferred con struction. but as illustrated in the drawingscomprises a steel outside casing with a firebrick lining A and a fillingof [ire-resisting material, as ashes or earth A, interposed between saidcasing and lirebrick lining. The furnace portion B is of a usualconstruction in most particulars, having two or morecombustion-chambers, with grate-bars 7) in each, and provided with adoor 6 to the space above the grate-bars and to the ash-receptacle Bor'space below said grate-bars. The ash-pit portion C is also suitablyconstructed of brick and has vertical flues a, leading from theashreceptacles B beneath the grate-bars to the ash-pits C in the lowerportion of the structure. Said flues preferably lead from the rear endof the ash-pits and are narrow, thus compelling the air to pass over theashes and through the length of the ash pit before reaching said fines.Doors 0 are provided to said ash-pits. A transverse archway is formedthrough the lower portion of said structure, and a tapered bottom A onthe lower end of the barrel of the limekiln extends therein. A valve ordoor a of suitable form is provided on the lower end of said taperedpart, by

which the contents of said barrel may be discharged.

On the right-hand side of the structure in Fig. 1 I have shown anapparatus including a fan 1, pipe 2, leading from the upper portion ofthe kiln, pipe 3, leading to the separator (Z, and pipes 5, leading fromsaid separator to the lire-boxes, which apparatus is adapted for usewhen force draft is required similar to that forming the subiect-matterof my former Letters Patent, No. 717 A59.

The doors 6', b and 0 illustrated are preferably similar to thoseforming the subject matter of my Letters Patent No. 745,249.

The doors 0 of the lower ash-pits C have openings which may becontrolled ordinary valves 0" for permitting the ingress of air from theoutside. The ash-pits 0 being at a considerable distance below theash-receptacles B and furnace (and this is an important feature of theinvention) and the heat therein being intense because of the hot coalsand ashes falling from the receptacles B thereinto, the air which comesthrough said doors a and passes through said ash-pits over the hot ashesand through the three a becomes heated to a point which will be nearlythe temperature of the combustion-chambers before reaching them and doesnot, therefore, tend to reduce the temperature of said combustionchambers. A higher temperature may thus be maintained in the kiln withless draft and fuel than would otherwise be required.

As is well known, the material in the bottom of the barrel of thelimekiln is of very high temperature-from 1,500 to 2,000" Fahrenheit andtherefore the space surrounding the lower end A of the barrel within thearch of the lower end of the structure is necessarily of a very highten'iperature. To utilize this heat, ordinarily wasted, 1 provideair-flues by means of pipes a or arches in the structure itself, theentrances to which will be on opposite sides of said bottom A of thebarrel within the arch, and form them to wind spirally around the lowerend of said barrel, as indicated in Fig. 2, and discharge'into the lowerpart of the ash-receptacle B beneath the grate-bars. The air taken fromsaid archway is of a very high temperature when entering said fines, andin passing through said flues around the barrel of the kiln is stillfurther heated until when entering the combustion-cham here it is alsopractically of the same temperature as said chambers. in some instancesforced draft will be needed, and I have also shown means for taking theair through the pipes a and into the fire-boxes under pressure. Saidapparatus consists of a fan 10, a pipe 11,1eading therefrom andconnecting with each of the pipes (0 and a pipe 12, leading from thefan-casing and having a branch discharging into the boxes B under thegrate-bars 7). A sliding valve (4* is adjusted to cover the mouth ofpipes a in the receptacles B when said forced draft is to be used. Bythis means the combustion-chambers are supplied with air heated to ahigh temperature whether operated under forced or natural draft, and thetemperature of the kiln is thus maintained more easily and economicallythan when the air is taken directly from the outside. By thisarrangement a natural draft is provided which in many instances issufficient for the purpose, and a forced draft provided for an emergencyor when the natural draft is inadequate, the efiiciency of the kiln isvery materially increased, and the expense of its operation lessened.

Having thus fully described my said invention, what I claim as new, anddesire to secure by Letters Patent, is-

1. A limekiln provided with a second ashpit at a considerable distancebelow the combustion-chamber and first ash-receptacle, and a fluerunning from said second ash-pit to said receptacle, air-inlets beingprovided through said ash-pit, substantially as set forth.

2. In a limekiln, the combination, of the lime-holding barrel, thecombustion-chambers, the ash-receptacles beneath saidc0mbustion-chambers, flues leadingdownwardly from said ash-receptacles,and second ash-pits in the lower portion of the structure connected withsaid flues, and valves for controlling the ingress of air through saidash-pits, substantially as set forth.

3. A limekiln structure, the lower end of the barrel whereof extendswithin an arch in the lower part of said structure having airfluesleading from the space between the lower end of said barrel and thesides of said arch and coiled around said lower end just within themasonry and arranged to discharge into the furnaces beneath thegrate-bars, substantially as set forth.

4. A limekiln structure having air-fines extending from the archwayadjacent to the lower end of the barrel, encircling said lower' end anddischarging beneath the grate-bars, valves to control theirdischarge-openings, a fan, a pipe connecting said flues with thefancasing and a pipe leading from said fan-casing to the fire-boxes,substantially as set forth.

5. In a limekiln, the combination of the kiln structure and a draftapparatus comprising coiled pipes or flues surrounding the lower end ofthe limekiln-barrel and leading from the chamber adjacent to said lowerend into the furnaces, the discharge end of said fines being providedwith valves whereby they may be closed, and the forced-draft apparatusconnected with said flues and adapted to draw the air therefrom anddischarge the same into said furnaces under pressure, substantially asset forth.

In witness whereof I have hereunto set my hand and seal, at lVashington,District of Uolumbia, this lth day of August, A. D. 1904.

SAUL W. SHOOP. [L. s]

Witness es:

MARY A. WILsON, K. HURsr.

